Machine tool



MACHINE TOOL Filed Dec. 14, 1943 5 Sheets-Sheet l PAUL A, POWELL, INVENTOR.

July 2,1946. P. R. POWELL MACHINE TOOL Filed Dec. 14', 1943 5 Sheets-Sheet 2 PAUL R. POWELL, INVENTOR.

July 2, 1946 AP. R. POWELL MACHINE TOOL 5 Sheets-Sheet 3 Filed Dec.

INVENTOR.

Illlllllll PA UL R POWELL,

w a a IIFIII m P F I m u 9 w W m. M a m w July 2, 1946. P. 'R. POWELL MACHINE TOOL Filed Dec. 14, 1943- 5 Shets-Sheet 4 FIG. 9. FIG. l0.

' PAUL R. POWELL, INVFNTOR July 2,1946. P. R. PWELL 2, 03,119

I MACHINE TOOL Filed Dec. 14, 1945 5 Sheets-Sheet 5 I:Illullnlllllllllllllllll I7 F/G. l6

FIG; /8. FIG /9.

PA (/4 R. POWELL, INVENTOR- FIG. 20; aif-kw Patented July 2, 1946 UNITED STATES PATEN T OFFICE MACHINE TQOL PauLRrPowell, Baltimore, Md.

Application December 14, 1943, Serial No 514,255 13 Claims. 21. 164-47) This invention pertains to the art of machine tools, and more particularly'to'the art of machinmachined to the desired contour can be operated in the machine as the templet. The machine'is capable of machining a piece of work to a predetermined contour under manual control, which piece is thereafter available to-be operated in the machine as a templet to' control the machining of one or more other like pieces successively to the desired contour. 2

The machine of the present invention, it will be readily understood, is primarily :a production machine, but'it is also operable as a model making machine. To persons skilled in the art of model making it is well understood that, in spite of the most careful and skillful calculations of size, shape and dimensions, a model will frequently turn-out to be inaccurate in one or more particulars. It is then necessary to rework the piece, or make new piece, in order to produce one machined to the desired contour. In the case of a piece to be incorporated in an assembly, for examplethe model will often fail to fit because of one or more dimentions being-off a greater or less amount. Reworking and revisions are then necessary, usually by a cut and try method, until a model is made to fit with the desired degree of accuracy.

The machine of the present invention is able to machine models to the desired contour more easily, more accurately, and at less cost, than is possible under the prior art practice. Furthermore, minor inaccuracies -in-the-model can be readily compensated "for. The machine equipped with means, adjustablewhen the contour of the templet is found-inaccurate, to machine work pieces accurately to the desired contour'under control responsive to the inaccurate templet; v i i j Although the invention is, of broader scope, the machine of the disclosed embodiment is constructed primarily for machining elongated structural stress members, such as beams, struts, stay rods, and the like. In the art of aircraft such members are positioned to intersectwith members they are joined with, their end surfaces being" attached, by welding or some, similar means, in

surface to surface engagement with the member intersected. Aircraft stress members are commonly constructed of lengths of tubing. Each end surface of a tubing member is machined to a contour tofit the surface of engagement with the one or more members it intersects. Thecontour of surface engagement at anend of a-stressi member tubing is determined by the contour of the surface intersected, and the angle of ap-" proach of the tube to the surface. The machine of the present invention-operates "to machine each.end of the tube length to the contourrdictated by the intersected surface, to fit' precisely in contact therewith. V

Usually both ends of apiece 'of tubing must be machined, each to fit a surface of intersection. Accordingly, thetubes mustxbe machined not only to correct contours at respectively opposite'ends, but they mustbe machined to proper lengths, and contours at opposite ends of a;given tube length must be disposed in correct relative circumferential registry. l The machine ofthe disclosed embodiment of the invention is'adapted to attain desired cone tours of end surfaces easily: and in a novel manner. Much of the prior art cut and try practice to attain a properly fitting piece, and the remaking of models to replace spoiled pieces, is avoided.

When the contour of the model is found not en-' tirely accurately cutto fit, the machine-can be adjusted to machine subsequent tube ends to ac curate contours, using the inaccurately machined model as a templet. When machining of opposite ends of the model tube is found somewhat out of accurate circumferential registry, the machine can be adjusted to machine the ends of the next tube to accurate circumferential registry using the ina'ccurate'model as the templet. If the length of the model is found to be'inaccurate, the machine can be adjusted to machine subsequent tubesaccurately to desired, lengths using the inaccurate model as a templet. o r

The machine of the disclosed embodiment includes a machining tool which presents a new result in the combination of the machine, and which embodies novelty, per se. The construction of the new tool embodies principles not found in tools of the prior art; The machining tool comprises companion male and female dies, constructed to afford advantages in strength, stress resistance; and cutting-action, which advantages "vention, attention is nowthereof. In the drawingson lin'e-aW-Bzof Figure of? thetemplet, andlongitudinally of the: mat-- parts broken away'for clearness;of,.illustration,

Figure, 2 is a view in perspective of'the top of the machine, directed to the working head,

Figure 3 is a cross-sectional elevation of the machining tool, taken through its center plane 7 longitudinally of the machine, on line 3-3 of Figure 4, a

. Figure 4-is a cross-sectional,elevation.taken..

} on line 4+4 of Figure 3,

Figure 5 is a cut away plan view showing the? machining tool,

Figure 6' is" a: cross-sectional;elevation;taken; 4; throughzthe center-plane:

Chilie,': L

Figure '7 isan, elevation of; the. intergearingg 3 between the=templetand the--W0rk=,,with parts;

broken. away, the, view being; indicated. line-v 1?'--1 in Figure 1,

Figure 8 is a. detail. cross.section,-, taken, on

Figure 9 is a.cross-sectionalnlevation;takenxon Figure: 10 is a" fragmentary view of: thewlatch; of'Fi'gure 9 in open position...

Figure .11 is a fragmentary plan view illustrat ingthetailrest;

FigurelZ is a cross-sectional"elevation-'takene. on-line 12 42. of--'Figureill, withrpartsf broken away for clearne'sstof illustration;

Figure 13 is a: cross sectional elevation. taken:

on line l'3'-'- I '3 iofFigurel'2g Figure 14'11isa fragmentaryrplan-tview' iHUSftIEttI- ingthemachining tool, V

Figure IS-isa fragmentaryrcrossi-seotiorrvtaken; on line l5-l 5 of Figure 16;

Figure 16ris a fragmentary?crossesectional;-e1evation takenon line l 6,-- Hi: ofEi'glllieifi-lly,

Figure' lT is a cross-sectionalelevatiorratakenz on line lil'l TofFigureglfi;

Figures 18; and 19 are perspectivezviews; from: the 'leftand right respectively, of thefmale dieg and:

- Figure= 20- is'? a perspective :view; illustrating-asmodifi'edform of machinin'gtooii;v

The machine of" the; drawings: practica1 application of: the principles of thez' i vention; It comprises the=bed plate-ill; Figure. 1, which carries the working headtgenerally illustrated at l2. See-also-Figure- 2; The-work ing head I2 is operated. by the-' driving mecha.-; nism, generally illustrated at..l4.,

The, working, head. comprises the2 machining; tool. which. operates. to machine. the, work, andillustrated generally, at It, Figure, 2.. The; work: ing head also includes mean operativeto. control the machining operation, illustratedv generally at' IS, the controlmechanism being located generally: forwardly; of the machining tool; as shown. 7 1

' The machining tool I6; of the disclosed embodiment, comprises the companion male and female-dies, l-Tand I8, respectively, Figures 3, 4, 5-- and 16; the male die beingreciprocate'd in'. the female die to perform-the cutting operation. The:

presentsjone;

. male dieisreciprocated by I the driving mech'a nism l4, Figure 1, which comprises the connectof shear edges at pposite ends,

' firstiatnaipointalongj thesheartedge 3] ing rod l9, driven through the crank 20, by the motor 2|. The connecting rod [9 actuates the reciprocating head 22, which is fixed to the tool carrying shank or arm 23, Figure 3, longitudinally lidable in the bushin 24. The bushing is held fixed within the supporting leg 30 for the bed plate II, which also houses the reciprocating mechanism, as shown.

The toolijattaching head zfi'fisaaremovably at- I tached to the arm 23 by the screw threads 26. The head 25 is reciprocated in the head stock 28.- The head stock rests on the bed plate ll,

heidxin position by the screws 29, which locate and fix the reciprocating mechanism housing 30,

? thebedplate l l, and the head stock 28, relatively positioned. SeeFig-ure 3.

The tool holding head 25, is enlarged as shown, toprovide an ample. mass of metal to support the shock strains of the cutting operation. It includesuthe extension-.3;l-, which provides abackingsupport for the-cutter:l:'|',jFigures 14, 1'5 and. 16. The companion :key: and; keyway r 3 2; between; theextension 3iv and: the-cutter; ll operatemo locate the cutter. properly, disposeditoperform:

its'function.

The: cutter; shown in. d tail; in' Figure 18; and 19, is symmetrically constructedto; present: pairs.

interchangeably. By reversing the :tool' ll in;the

head 25; either one: 0117' the; other "of the shearing.-

edges 36, 31 can b'eupositionediioroperation;

The cutter comprises: the: nose,35:,.projected laterally: of the axis of: the: head. 25; the nose: being rounded to: a. predetermined; curvature.

Figure, 14. The nose;presents;thez'overhangingv shearing edge 36'. The; side cutter; comprising the additional overhanging: shearing edge:

As: will bezclear. from: Figure; 116, the: shearing? edge-; 31 is cantedatran angle-directed downwardly from the .n'ose. 3.5;iwhich2contribi1tes to therdistribution of:theicutting;shock-. During the. cutting stroke; contactis madewith the.- work. nearthe axis: of the shank 2331 Contactrprogresses. along: the shearing edge, 31: awayfrornthe axis o-fr'the arm zii'towardscthe nose 35, the cut beingcome p letediby the rounded edge 36." The shock'of'the cutting operation is thus distributed along the shearing; edge 36,. 31;

Another object of the-elongatedshearing edge 36-, His to provide an extended'mass of metal'to withstand the shock of the cutting operation. Themetal mass being extended longitudinally, a lesser. thickness of metallis required-longitudinally of the stroke to back the shear edge 36, 31, and accordingly the cutting edge is located closer tothe end of the cutter FL. This enables tubing of smaller-diameter to be machined.

Thenose of thecutterfifi isdirected away from the'axis of the'shank- 23, transversely-thereof towards the work piece 5'0'; and 'i'n the" caseof the-workpiece being tubing, as shown, the nose is projected into the end of the tubing, directed longitudinally thereof The-elongated shear edge 36; 31, andthe correspondingly thinner mass of metal backing the shear edge', permits the smallest-standard size stress tubing to he'machined by' the disclosedmachine'ot the present invention.

The duplicate sets of shear edges 36, 31, at

'whichare'usable 31, is; continuouswith the shearing edge 3% ofzthe anoseg.

. ratio between the gears 95 and 96 is 1 7 tively, are positioned on the plate 85, and when so positioned the knurled knob 81 is rotated to close the pairs of jaws 8|, 82 and 83, 84 into engagement with the work and templet pieces. When adjustment is made, the jaws are held in adjustment by the set screw 9|.

The pairs of jaws 8|, 82 and 83, 84 are spaced apart the same distance as the holes 13 and 14 of the head rest 51, whereby the work and templet pieces 58 and 68 areheld in parallel relationship, the spacing being the same as the dis]- tance between the cutter I1 and the templet follower I 81. V

To operate the machine, it is first used to machine a model. A head rest 51 with the proper sized holes 13 and 14 -for the given tube size is selected. The head rest is adjusted to the preferred spacing from the cutter I1, by means of the bushings 66, and the tail rest 58 is adjusted to the proper position along the parallel ways 56 for the tubing length. A tube of proper size and length is now placed clamped in the hole 13 by mean of the latch 1|, and knurled knob 81 is rotated to adjust the jaws 8|, 82 into engagement with the tube. The cutter I1 is now set in operation driven by the motor 2|, and the tube 58; is slid longitudinally in the hole '13 until it comes into machining engagement with the cutter. The

tube 58 is manipulated manually to machine its ends to the desired contours. dinally in the hole 13 to attain the desired depth of cut longitudinally of the tube, and it is rotated to attain the desired circumferential contour, rotation being towards the operator, or in the clockwise "direction in Figure 2. I When one end of the tube has been machined to the desired contour, the tube is reversed in the hole 13, and the other end of the tube is machined in a similar manner to its desired contour.

It will be noted that the tube can be readily removed from and replaced into the machine to try it for fit, by sliding it out of and into the hole 13. Thus, complex contours can be attained to a high degree of accuracy with a minimum of work.

The machined tube 58 is now positioned to become the templet tube 68, by being positioned in the hole 14 of the head rest 51. A new tube 58 is positioned in the hole 13 as a work piece. Preparatory to being so positioned in the machine, the work and templet pieces 58 and 68, respectively, are intergeared to rotate in unison, the intergearing 94, Figures 2, 3, 6 and '1, being provided for this purpose. v I The intergearing, illustrated generally at 94, comprises the gear 95, attachable to the work piece 58; and the gear 96, attachable to the templet tube 68. Adaptor bushings 98 of various required sizes are provided to adapt the gears 95 and 96 to tubing of any desired size. The gear to 1, and the drive is through the idler pinion 99, whereby, when either tube 58 or 68 is rotated in its hole 13 or 14, respectively, the other tube is rotated to the same extent in the same direction.

. The gears 95 and 96 are enclosed in a housing, comprising the inside plate 15, which spaces the tubes apart the distance predetermined by'the distance between the cutter I1 and the templet follower I6. The inside plate 15'provides a journal bearing for each of the gears 95 and 96, and a bearing pin 16 for the idler pinion 99. The cover plates 11 complete the housing of gear96, in the manner illustrated in Figure 7, being attached to opposite faces of, the inside plate 15 by It is slid longituplate 8' screws 18. See also Figures 2 and 6.. The. gear 96 is attached to the bushing 19,.as illustratedin Figure 6, b means of screw 88, the bushing19 providing a flange, as shown, for attaching the gear 96 to the templet-tube 68, by means of the set screw 91, which passes through the adaptor bushing 98, keying it to the bushing 19 and the gear 96.

The knurled nut 92 is disposed on .both faces of the gear 95, as illustrated in Figure 3, to complete the housing thereof, and of the pinion 99. See also Figures 2 and7. The knurled nut 92- is fixed to the gear 95, by screw 93, to rotate therewith in thrust bearing engagement with the inside plate 15. The knurlednut 92 provides a flange to attach the gear to the tubing 58 by means of the set screw 91, Figure 3, which passes a through the adaptor bushing 98, keying it to the gear 95.

Now referring to Figure 2 it will be noted that, when the knurled nut 92 is rotated manually, the rotation is transmitted to the tube 58. This operates to rotate the tubes 58 and 68 in like directions to the same extent, through the intergearing 94. I

The, tubes 56 and 68, with the intergearing 94 attached to them and attaching them together, constitutes a unit. Preparatory to placing them in operative position in the machine, the ends of the tubes are adjusted in alignment.

Mounted to pivot at I8I on the bracket 62, Figure 2, is the locating bar I82, which can be swung down across the ends of the tubes 58 and 68. With the ends of both tubes in engagement position, and the intergearing 94 is fastened in position by tightening the set screws 91. -The bar I82 is canted at a slight angle, to make the tube 58 project slightly further than tube 68, to allow for machining. When adjustment has been made, the bar I 82 is lifted to inoperative position shown in Figure 2, and the machine is ready to machine the ends of tube 58 to the same contour as the ends of the previously machined tube 68. The templet. follower I5, illustrated in detail in Figure 6, and now to be described, is provided for the purpose.

The templet follower comprises the plate I85, Figures 2,4 and 6, which supports the upright bracket I 86. The bracket I86 carries the roller I81, rotatably mounted on the pin I88. The roller I81 preferably has the same radius as the radius of curvature of the nose 35 of the cutter I1, and the surface of the roller I 81 lies in the same vertical plane transversely of the machine as the tip of the nose 35. This'causes the machining of the end of the tube 58 to be an exact reproduction of the contour of the end of tube 68.

The bracket I 86 projects upwardly from the I85, as illustrated in Figure 4, to suspend the roller I81 directed downwardly in the path of the end surface ofthe tube 68, contact being made at the upper element of the tube. See Figure 6. The lower end of the roller I81 is spaced above the surface of the plate I85, which apart bythe cutter 3 ground away as shown;

chine,

piece: 50; mlparallel relationship,

2, 4oa-1 re oppositeends of thecutter tool l1; and spaced shank- 3'8;- facilitate fastening the butter" to-the head25. Thetool shank; 38lisv i to provide the required. undercut-for the shearedge 36; 3 1, theextent' of undercut determining the depth of out.

When the cutting head i's positioned-in themawith one shear edge 36, 31 disposed in cutting position, the ledge of the other shear edge is engaged by the'shoulder M- of the hold down plate 42,- which is attached to-thehead 25 by' theset screw 431 The locatin platet engages the "surface-39 of the cutterfl opposite the hold? down; plate 62-; tofix the cutter in position in theheadf; The-plates and; cooperating withthekey and-keyway-BZ; hold the cutter |T- firmly attachedto the'head 25; and in turn are heldfi'n-position by the sleeve 21-, which to the head 25 by the set screw 40, Figure 1'7;

The-plate 51, Figures E l -351C116, is attachedto the top-surface of the head stock'28', held in position bythe screws 52 and 53*. The plate iii-providesbearing surfacefor extension 3| opposite nose -of tool H, bearing contactbeingon the:

surface of the head :25. The plate 5| aiso locates the female die I la in proper position relativewthe cutterll, the set screws 53- operating to hold the die l8in posit-ion.

The-female die'l8 as will be seen in Figures 14 and 16, presents itstopsuriace as a-rest for the work 50, the inside edge of the top surface of the'die I 8-presenting the shear edge 54, compan ionwith-the'shear'edge 36 31 of the male die 11, and cooperatingtherewith in shearing. action.

Thefemale die'presents a surface along its inside-border'companion to the surface- 39 oppo site"theoperative shear'edgesfifi', 3-1; andby this means the dieiBsupports themale die I! against lateral thrust under 'shock'of the cutting operation. It' willbe noted that'the tool mounting; comprising the head 25, the attachment of I the die-i8; and the key and keyway 3'2 cooperating; with theholding and locating plates 42 and 4:4 to hold the rmale die IT; presents asturdy; con: struction toenablev the' tool I 6 to carry the shock of the cuttingoperation.

The plate M is notched; asillustrated in Figures IB'and' H, to receive chips asthey fall; one. with-eaclr-downward stroke of.the;cutter. H. The. chipsf'allfrom theplate' 4 into andflthroughthe chute 45in'the headstock 28, onto the, inclined bed 46 of the block il; Figure 3. The block: is attached-o to the arm; 23, as shown, together withthe surrounding-sleeve 48, which confines the chips" to prevent their falling between. moving parts where they can do damage. The set' screw, 34 holds the block 41 and the sleeve 48 fixed to the arm 23. The block: 41 travels with V the base 55, whichrrestsin fixed position onthe.

bed" plate H.

The; work is carried'between the head rest, i1; lustrated generally at 51, and the tail rest, illustrated generally at 58, Figures 1 and 2. The head" and tail rests; 51 and 58, also carry the lternplet tube. which operates to control machining oft'h'etends of) work tube 59 to predetermined desired contours; The head and tail rests 51 and 58; respectivelyglhold the templet piece Bil and the work: directed: towards the-templ'et follower I 5 and the tool l6} respee V tiveiyz I i The head stock 28 extendstransversely ofitheat the front and rear respectively, Thefront-bracket :61 "carries the pin 6 3; Figure 1 and therearbracketcarries the pin 64, Figure 9. 'I'he-pinsN and fi'i'support the jaw'member 6i", attached' theretobythe nuts 65'. The spacer bushing- 66 can be adjustablypositioned' on the-pins$3 and 64- tolocatethehead rest- 5? a predetermined greater or lessdistance from the head stock 28, The jaw member 681 is pivoted to the bracket 69 at ill, thebracket 69 being fixedly attached to the-jaw member 6] in any suitable manner} See Figure 9. Thelat'ch 71; illustrated inopen position in- Figure 10 and" in closed position in Figure 9, operates tohold-the jaws 61 andi68'in with each other The pair of'jaws 61; 68 haveholes T3 and I4;

closed position in engagement each; hole comprising a semicircular notch in each of the jaw' members 61 and 68. The holes 13 and 14fh01d the work-pieceifl and the templet piece 60-; respectively, ,to-maintaintheir head ends spaced apart a predetermined" distance, and; at

a predetermined level;' The hole 12 in the jaw member 61', which engages the pin 64, is slotted vertically' 'to vary; the height of the head rest 51, for slight adjustment or 60 which may befoun dj necessary. The holes I3 and 14 are of sizesfto hold-the'work 5ii-and the templet 60 against" appreciable lateral movement in any direction, butare sufliciently oversiaed to'permit rotation'of the tubes, an'd longitudinal slidingin" the: holes: I

It being contemplated-underpreferred practice of the invention thatthe templet be va previously machined work piece 50 the holes 13* and'l'lt are ofthe samesize: A headrest 51 of-proper'siz ed holes- 13" and ltl is provided for eachzdiiferent 'si zer tubing tobemachinedon'themachine. v 7

It isd'esirablethat 'thehead', rest 5'! be position'ed asnear as'possibleto the cutter Hi, to minimize the tendencyofl the workpiece '50., to chatter or pushlaterally under the force of the machining operation: The spacer: bushings 6E7 allowfor adjustment, to enable the head rest 51. t'obe positioned as near as possible to the tool for the maximum stead'ying, but as far away from the end of the-tube Wasisnecessary to clear, the machining, the rangeofladjustmentpossible with the bushings 66 being sufficient to clear themost extensive longitudinal contour-to be machined.

The tail rest 58 comprises the pairs of jaws 1 83; Bil like amountssirnultaneously. The reversely threaded screw 86 is beari'ngedin the housing bracket B-Btwhichis mounted movable longitu dinally of the" parallel ways" 56 to adjust the 1 machine-to accommodate anydesiredlength oftubing; The-bracket is held in positionof adjustment along the ways-'56 by the clamping plate 89; which is fixed in clamping engagement with;the* paralleliw-ays by the set screw 90.

The work andg-templet tubes, 50- and' Bil respec the level of tubes 5!). and

.cause the roller cut a notch longtiudinally of the tube until the end of the templet tube 60 engages the roller I01. Now the knurled nut 92 is rotated towards the operator to feed the tube 50 to the cutter IT. The tube 60 rotates in the same direction to a like amount, and simultaneously urged into engagement with the surface of the roller I'I, the contour of the machining of tube 50 thus being controlled to be the same as the end of the tube 60.

One end of the tube 50 having been machined, both tubes and the intergearing 94 are removed from the head rest 51, and are repositioned therein in the reversed position, for machining the opposite end of the tube 50 in accordance with the contour of the corresponding end of tube 60. The adjustment of intergearing 94 has not been disturbed, and accordingly'the tubes\50 and 60 continue in longitudinal adjustmentirelative to each other. Accordingly, tube 50 will be machined-to the same length as tube 60. Also, the machining at opposite ends of tube 50 willbe in the same circumferential registry as the opposite ends of tube 60.

It sometimes happens that the templet tube is machined slightly too short to fit in the assembly. The machine of the present invention is adjustable to obviate the necessity to remachine a new templet tube accurately to the right length. The carriage plate able longitudinally of the tube 60. The stud I09, threaded into the head stock 28, carries the knurled nut IIO, which includes a collar straddled by the fork III of the plate I05. See Figure 6. Rotation of the nut IIO advances the plate I in the guideways H2 and I I3 of the guide plate H4, to adjust the position of the roller I01 longitudinally of the tube 60.

The guide plate II4 rests on the headstock 28, fixed thereto by the set screw I I5, Figure 4. The slotted guideway IIB enables the guide plate to be moved transversely of the machine, in adjusted position nearer to or farther away from the cutter; I1. By means of this adjustment the roller I 01 can be positioned to contact the tube 60a predetermined circumferential distance in one or the other direction from the upper dead center thereof. When the model tube 50 is found to be machined slightly out of circumferential registry atits opposite ends, the plate II4 can be relocated longitudinally of the guideway H6 to I0! to contact the end of tube 60 a compensating distance awa from upper dead center. By this means opposite ends of the tube 50 can be machined in accurate registry without the necessity of remachining the original templet to accurate registry. I v A modified and simpler form of machining tool is illustrated in Figure 20, this being a less costly embodiment suitable for some classes of work,

The machining tool of Figure comprises the male 'die I 20, which is preferabl cylindrical, and which is operated to reciprocate in the circular hole in the female die I 2|. The male die I20. is provided with the downwardly directed shearing edge I22, which cooperates with the shearing edge I23 of the female die I2I. Opposite the shearing edges I22 and I23, the male and-female dies present companion cylindrical surfaces I 24 into engagement with each other, the bearing surfaces I24 operating to support the tool against the shock of the machining operation.

It will be noted that there is a relatively small mass of metal to withstand the shock 'of the cutting operation, and accordingly, in this emmachine, and of the I05 is mounted slidbodiment it is usually end I26 of the male die beyond the shear edge I22, and to ride the end I26 in the supporting sleeve of the arm I21 which is mounted in fixed position on a stationary part of the machine in any suitable manner. I

The, tool of Figur 20 is suitable for machining tubes of large diameter and thin walls. The lower cost of the tool of Figure 20 warrants the modification. 7 Having described the nature of the invention in detail, it willbe noted that the invention is not limited to the embodiments shown in the drawings, but its scope is determined by the accompanying claims.

I claim:

1. Apparatus for machining the end surfaces of a length oftubing to predetermined contours, comprising the combination of a tool operable around the tubing to machine the tubing ends, and means to control the machining operation in accordance with the, desired contours, the control means comprising a tubular templet and atemplet follower relatively movable in engagement with each other, and mechanism to direct the machining operation responsive, to the relative movement between the templet and the follower.

2. Apparatus for machining a plurality of pieces of work to predetermined like contours,

comprising the combination of a tool operableto machine the pieces individually, and control means comprising a templet and templet follower relativel movable in engagement with each other, means under. manual control to direct machining of a given piece to. the predetermined desired contour, means to operate the machined piece as the templet in the machine, and mechanism to direct the machining of subsequent pieces responsive to the relative movement between the machined piece and the follower to machine the several subsequent pieces to the same contour as the machined piece. 9

3. Apparatus for machining a, plurality of pieces of work to predetermined like contours, comprising the combination of a tool operableto machine the pieces of Workindividually, and control means comprising a templet and templet follower relatively movable in engagement with each other, means under manual control to direct machining of a given piece to the predetermined desired contour, means to operate the machined piece as the templet in the machine, mechanism to direct the machining of subsequent pieces in accordance with the contour of the templet piece -in response to the relative movement between the templet piece and the follower, and means operable When the machining of the templet piece is found inaccurate to adjust the control means to compensate for such inaccuracies and to machine subsequent pieces accurately to the desired contour in response to the relative movement between the inaccurate templet piece and the follower.

4. Apparatus for machining the opposite end surfaces of a length of tubing to predetermined contours having predetermined circumferential registry relatively to each other, the mechanism comprising the combination of a tool operable to machinethe tube ends and means to control the machining operations in accordance with the desired contours, means to adjust the control means to determine that the machining operations at opposite ends of the piece are in desired circumferential registry.

5. Apparatus for machining the end surfaces advisableito elongate the means to control the machining operations in accordancewith the "desired contours, the contifoli means comprising a templet"andter'riplt' folloyver,'=-the templ'et comprisin'gapreviously machined tube,the "tern'plet "and "tei'nplet follower b'eing'movable 'r'elative'to 'ea'chothe'r' Withfthe'fol- 'lo'v'rer in engagement With' the en'd"surfaceiof the tube, intergearingbetween' the t'mplt tube and the Worktnbe to rotate trieminnmsontc machine the Work tube res onsive to the templet tubefandfollowi. I 'npparatus'ior ma'cniniiigtiie endsiirfa'ce or a" tubular Work pi'c'eto'a'predeter'mined desired contour; comprising "a' 'malohinilig" tool, a tubular templ'et piece like the workpiece "with an end Cphtbfir corresponding With the desired fin'toilr ofthe'fworkpie'cefa' templet fol-lower, and means supporting the Work piece with itsends "directed tothefiwchiniflg' toolat one portion of itsperi'rmeral fare and thete nplet 'pi'ece"with'its 'end directed't'o theffollowerlat the corresponding oppositeportion' of its peripheral arc;

"*8; "Apparatus for machining *apiece of work,

comprising a machining tool andm'eans Y to feed the i'rorktothe moi, the toolcom'prising a female die and a male die longitudinally -movabl'e in shearing engagement therewith; the "male die comprising -a cutter head and an actuating'shank, thec'n'tter head comprising an elongated shearcutting'e'd'ge at its "side extending'frommear" the axis 0f the shank transversely ther'eof aifdffa roiin ded nose wit-ha cuttingedgecentinuous'ivith the side cutting edge, the "nose 1 being "directed towerds thewon pieceQ-thefemaIe-die comprising "a work support surface, I prising a cutting edge companion to' the continuous; sideand nose'cuttingedges ofthemale die, "the c utting edges of the male -and female-dies being relatively positioned for shearing action longitudinally of "the when the male die" is moved axisof 'the shank.

h of tubing to' predetermi ned contours to control the machining oper- 'the'border-therof coin periphery thereof, the

"cutter head comprising K 7 t -fer nale "die'coin'prising a surface to support the workpiece at its end, the

bor'd'e'r of the fe'rnale die, comprising "'a'cutting edge companion V "cuttingedgesof the maledie,'jthe cutting edges to the continuous side I and nose of the male andfeiriaie dies beingrelativly positioned for shearing action when themaIe-fdiis ting edge at its sidepitending from'near the "and a male die ing engagement axis of the shank transversely thereof and a rounded nose'with acutting edge continuous with the side cutting edgefthe female die comprising a Work supporting surface, the border thereof comprising cutting edge companion to'the continuous side and-nose cuttingje'd'ges of the male die, the cutting edges ofthemale and femaledies being relatively positioned for shearing action when the male die is moved longitudinally of the axis of the shank. V V

11. A machining tool comprising a female'die longitudinally movable in sheartherewith, the male die compris- [ing an actuating shank and a cutter head at- 9. Apparatusfor machining theend surface-of a tubular workpiece, comprisinga machining tool andmeans to feedthe end of -the' work piece -to the tool, the tool comprisinga female-die and-a male die movable longitudinally inshearing' engagement therewithgthe male "die comprisinga cutter head and "an actuating-shankdisposed transversely to'the direction of the tubefthe cutter head corn-prising I edge at its side extending; from near the-axisjof the {shank transverselythereof-terminating with a rounded nose-witha cutting edge continuous '--With the side'cutting edge, thenose being directed longitudinally of the tubular piece Within "the an elongated shear-cutting tache'd'thei'eto at the end thereof, the cutterhe'ad comprising an elongated shear-cutting edge atits side extending from near the agis of the shank transversely thereof'and' cutting edge continuous 'with the side cutting edge, the continuous side and nose cutting" edges being directed towards the'shan'k,the female die comprising a Work supportingsurface, the border thereof comprising i a continuous side and nose cutting edges companion tothe cutting edge of the male die, the cutting edges of the male and female dies being relatively positioned for shearing action by the male'die being pulled bythe shank longitudinally ofits axis,

12. A machining tool comprising a fixed member, 'ac'utter head and an actuatingshank'fixed to the'cutter head, and reciprocable longitudinally of its axis'relative to the fixed member, the cutter head comprising an "elongated shear-cuttin'gedgeat-its side extending from near the axis "of {shank transversely thereof and a rounded nose withya cutting edge co tinuous with the side cutting edge, the "cutterhead 'alsocomprising a bearing'su'rface disposedopposite the continuous side and; nose cutting edges-the fixed member comprising a'bearing surface companion to the "bearing surface of the cutter head, to support the tool against the shock of the cutting'acti'on.

13. A cutter comprising overhanging cutting 'edges-spaced'apart'a opposite ends thereofleach cutting'edge comprising a side portion and a nose portion, each'sideportion comprising an elongated shear cutting edge extending from near the lon'gitudinal'a iisof the cutter transversely thereof to the 'noseportion, the'n'ose portion being rounded and extending continuous with: the side cutting edgefeach cuttingedge' being engageable to "hold the cutter in operating positionrwith the other cutting edge positioned for the'cuttin'g operation. I t V "PAUL R. POWELL.

a rounded nose with a 

